Do you think as fans we get hung up too much on the idea of a 20 goal a season striker? Statistics from the Premier League era are quite interesting: http://hitrowz.com/2013/07/14/the-myth-of-the-20-goal-a-season-forward/
For me the the term " 20 goal a season man" is a figure of speech and doesn't literally mean 20 goals .... For me it means a main Striker who will always be a goal threat, a player the other team worry about, a player who is capable of getting 20 goals in a season but will still get you 12-15 goals if having an average season. Obviously your interpretation will depend on who you support, the above is how I interpret it as a Mid table Fulham Fan if I supported Man City and we had just paid £40 million for a striker I might expect him to get literally 20 goals
I think the phrase '20 goal a season striker' is a bit of a hangover from the days when teams played more matches. In the lower divisions, where there are 46 league games, not 38, it's still a meaningful target for most clubs. In the Premier League, I think 15 is probably a more realistic target for the main striker for most teams.
When I think of a season I automatically think of cup games too. This is why big teams need 20+ goals a season strikers, as you need 100 odd goals just for the prem. Then maybe 25+ for Champions league, league cup and FA cup.
I think it's more about goals from midfield rather than a 20 goal a season striker, this is where Everton have excelled over the past few years. I can't remember the last time they had a striker who scored 20+ goals for them but in the shape of Fellaini, Pienaar, Baines, Osman and formerly Cahill, they have plenty of goals not just up front. If they were to get a 20+ goal a season striker (Thought Jelavic might be that) they could get top 4 easy.